Yeah, you don't need speaker cloth for bass traps, or first reflection panels for that matter. As Ethan always said, if you can blow through it with your breath and feel it on the other side with your hands it will work. Many people use even burlap material for bass traps. Bass freq's go right through. I would not pay extra for speaker grill material, JoAnns or even places like Walmart should have some black stretchy material much cheaper.

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